1. Field of the Invention
This invention relates to an improvement and simplification of the domestic and/or commercial machine washing of soiled textile articles by a process in which the aqueous washing liquor is formed in the presence of the soiled textile articles in such a way that a concentrate containing detergent constituents and in particular surfactants, is added directly to the dry or slightly damp textile articles and the washing liquor is formed in situ preferably by the gradual addition of water and rotation of the textile articles. The subsequent description of the invention is provided relative to the usual domestic washing machines of today. However, its essential process parameters can be used to advantage in the same way for commercial washing in corresponding laundries or washing plants.
2. Statement of Related Art
In practically all types of washing machines in use today the formation of the washing liquor takes place as follows: a measured amount of detergent is put into a dispenser and from there it is flushed into the machine by the water flowing into the machine. In a comparatively short initial period the desired end-concentration of the washing liquor is formed, in which the washing process is then carried out.
The detergents to be found on the market today are usually solid, crumbly powders, granulated substances or pourable liquids. The use of liquid detergents containing surfactant can cause difficulties in the usual domestic washing machines used in Europe because the soap dispensers which are available to take up an amount of powder are not however suitable for holding liquid concentrates there until they must be flushed into the body of the machine at the desired time of the washing cycle.
The prior art provides two basic ways for solving these difficulties. The first method is described, for example, in European patent specification No. 0 040 931. Described therein is the addition of a quantity of liquid detergent concentrate such that this concentrate is packaged in closed bags which are added to the textile articles before the start of the washing process. In such case the liquid detergent concentrate is packaged in a thermoplastic bag which is insoluble and impervious to water, and which, however, is closed by a mechanically weak hot seal such that this seal opens under mechanical action in the washing machine. This opening of the predetermined fracture location in the dosing bag should preferably take place within the first 5 minutes, and particularly within the first 2 minutes, after the start of the washing process.
The other proposed solution of the prior art is described, for example, in German patent application No. 35 12 050. Here, a process for cleaning of articles to be washed in a washing machine with a liquid detergent is described which is characterised in that the detergent concentrate is put in a dosage container which has permanent openings, for example, in a suitable dosage container in the shape of a ball. This dosage container, which is filled with detergent concentrate, is placed with the textile articles before the start of the washing process. If the washing cycle in the machine is then carried out with rotation of the textile articles in the usual way, then the liquid detergent concentrate is gradually dispensed from the container into the washing medium. The dosage container is removed from the machine after completion of the wash cycle and can be re-filled with liquid detergent concentrate and used again.
Both proposals of the afore-described prior art claim the advantage over the conventional use of the soap dispenser that fewer or no losses of detergent or detergent concentrate occur in the liquor sump, which according to present knowledge of machine technology can always form if the detergent concentrate is flushed into the machine with a little water and in this form sinks into a liquor sump. Additional means are needed, for example, the deliberate pumping around of the liquor sump, in order to prevent the loss of detergent components arising because of this in the main cycle of the machine process.
An object of this invention is the further improvement of textile machine washing wherein the detergent concentrate is directly added to the textile articles, and the formation of the washing liquor takes place in situ by the addition of water to the soiled textile articles containing the detergent concentrate.
A particular object of this invention is to provide the possibility of eliminating dosage elements such as packing bags or permanently open, re-usable dosage containers of the type previously described. In contrast, the teaching of this invention is based on the concept that a detergent concentrate is added to the textile articles to be washed as a substance at least to a large extent stable in form at room temperature, or on an article of textile which serves as a dosing agent, and the washing liquor is then formed in situ by the addition of water.